<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
</head>
<body>
<div>
    <h1>Hello World!</h1>
    num1: <input id="num1"/> <br/>
    num2: <input id="num2"/><br/>
    <button  id = "btn" style = "background-color: #2486ff">求和</button><br/>
    结果: <h2></h2>
</div>
<script src="./test.js"></script>
</body>
</html>
